It was proposed by Ernst Munch, a German plant physiologist in 1930. The evolutionary journey of plants onto land involved the differentiation of the plant body into decentralized organs, such as leaves, roots, stem, and branches. According to the pressure-flow hypothesis of phloem transport, _____. b) turgor pressure gradient. A plant cell with a Ψs of -0.65 MPa maintains a constant volume when bathed in a solution that has a Ψs of … solute moves from a high concentration in the source to a lower concentration in the sink Which one of the following statements about transport of nutrients in phloem is correct? Before moving into the source cells present in the phloem, the prepared food is converted into sucrose. Water moves from the xylem vessels into the adjacent phloem, thereby increasing the hydrostatic pressure in the phloem. d) osmosis and diffusion . Mass flow hypothesis? Name the form of carbohydrates which is transported in plants as food. An active removal of … Name the process by which sucrose is moved to companion cells and sieve tube cells of the phloem according to the pressure flow hypothesis. Photoassimilates and other solutes enter the source end of the sieve tube and attract water by osmosis. Pressure-Flow Theory for Nutrient Transfer. As the sink cells pull the solute out of the phloem, water leaves the phloem by osmosis, passing to neighboring tissues that have higher solute concentrations. These organs are interconnected at the whole-plant level by long-distance transport. 10. PHLOEM PRESSURE AND THE MÜNCH HYPOTHESIS: THEORY According to Münch (1927), long-distance transport is driven by osmotically generated hydrostatic pressure (phloem pressure). According to Annual Review of Plant Biology, 8. The active (energy driven) transport of sugars and other solutes into the sieve types in sources areas. See Section 35.4 (Page 739) . Long distance transport in plants occurs in sieve tubes of the phloem. According to the pressure-flow hypothesis of phloem transport, _____. Photoassimilates and other solutes enter the source end of the sieve tube and attract water by osmosis. According to the pressure flow hypothesis, food is prepared in the plant leaves in the form of glucose. The phloem tissue is the principal sugar conductive tissue in plants. Which is the most abundant solute in phloem sap? Besides water, sugars are one of the most important components involved in this transport. E) Sugar transport does not require energy. The relevant points of pressure-flow mechanism are as follows: 1. sucrose glucose starch amylose 9. There are different evidences that support the hypothesis. It is the aim of this paper to construct a mathematical model based on the Münch pressure–flow hypothesis that can reproduce these qualitative observations of phloem transport. This model of how phloem works is … kvargli6h and 50 others learned from this answer "The movement of water into a nutrient-rich region of the phloem decreases the pressure in that region" is the statement that is not true according to the pressure-flow hypothesis. The flow is generated by osmosis. According to mass or passive flow hypothesis, two features are important for phloem transport of substances. At present, it is generally agreed that P protein agglomerations are preparation artifacts due to injury, the lumen of sieve tubes is free of obstructions, and phloem flow is driven by an osmotically generated pressure differential according to Münch's classical hypothesis. Firstly, there is an exudation of solution from the phloem when the stem is cut or punctured by the mouthparts of an aphid, a classical experiment demonstrating the translocation function of phloem, indicating that the phloem sap is under pressure. According to the pressure flow hypothesis, food is prepared in the plant leaves in the form of glucose. It involves continuous entry of sugar molecules at the source and exit at the sink by active transport, together with the entry of water by osmosis into the source and exit out of the sink. c) osmosis. Water moves from the xylem vessels into the adjacent phloem, thereby increasing the hydrostatic pressure in the phloem. In angiosperms, increasing evidence shows the pressure-flow hypothesis, formulated by Ernst Münch in 1930 [1 ••], to adequately explain the mechanism of phloem transport [].However, its applicability to gymnosperms is more debated than ever. After sugars are produced in photosynthesis, these sugars must be transported to other parts of the plant for use in the plant's metabolism.Part of the pressure-flow theory is that the sucrose produced is moved by active transport into the companion cells of the phloem in leaf veins. (leaves) II. 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